The present invention relates generally to a cooling systems for an internal combustion engines, and more particularly to an auxiliary or supplemental heat exchanger or cooling system for use in conjunction with a main conventional heat exchanger or radiator-type cooling system.
As being known, internal combustion engines, and the motor vehicle industry employing such engines fall within federal governmental regulations, for example, the Environmental Protection Agency (EPA), which mandate that emissions such as NOx emissions be reduced. One scheme or mode of operating internal combustion engines which has reduced NOx emissions has used exhaust gas recirculation (EGR). Another scheme or mode of operating internal combustion engines which has been used to increase power is to provide increased cooling of the incoming turbocharged air being introduced into the engine intake manifold.
One way to achieve such increased cooling of the incoming turbocharged air being introduced into the engine inlet manifold is to increase the size or density of the main engine heat exchanger or radiator-type cooling system. In effect, more cooling surface area is provided within the heat exchanger or radiator and greater cooling is provided. Conventionally, an internal combustion engine vehicle has a single or main heat exchanger or radiator-type cooling system for performing or satisfying all heat load requirements of the engine. For example, those attendant the water jacket, the hydraulic systems, the power train, and the like. However, such an increase in the size or density of the main engine heat exchanger or radiator is not always possible considering size constraints or limitations for housing the main heat exchanger or radiator upon or within a particular vehicle. In addition, such an increase in the size or density of the main engine heat exchanger or radiator entails a substantial increase in the resulting pressure drop across or characteristics of such heat exchanger or radiator which, in turn, necessitates increased power input levels or requirements in order to achieve sufficient air flow through the system. Such increased power input requirements or levels can be attained or met, for example, by increasing the speed of the main engine cooling fan. However, increasing the speed of the main engine cooling fan results in enhancing noise levels which may also pose compliance problems with respect to current Environmental Protection Agency (EPA) regulations.
In some applications, an air-to-air aftercooler or heat exchanger is used to increase the density of the intake air. For example, in some on-highway applications, the air-to-air aftercooler or heat exchanger is positioned in line with the vehicle radiator or main heat exchanger.
Exhaust gas recirculation (EGR) of a portion of the engine exhaust gas from the engine exhaust manifold back to the engine intake manifold is a technology that has been employed to help reduce harmful exhaust emissions from an engine. However, the high temperature level of such recirculated exhaust gas poses a problem with respect to the performance, longevity and emission output characteristics of the engine. Therefore, such recirculated hot engine exhaust gas needs to be cooled prior to ingestion into the engine intake manifold. However, if such cooling of the engine exhaust gas is to be conducted or performed by the main engine heat exchanger or radiator system, the aforenoted size constraints, size limitations, power requirements, and noise level disadvantages or drawbacks characteristics of conventional engine heat exchanger systems would still need to be addressed.
In applications requiring additional cooling over and above that of today""s conventional engine, the size constraints, size limitations, power requirements, and noise level disadvantages or drawbacks pose problems and must be addressed by other non conventional apparatus.
The present invention is directed to overcoming one or more of the problems as set forth above.
In one aspect of the invention a cooling system is adapted for use with an internal combustion engine. The internal combustion engine has an engine block, an air intake manifold, a at least one turbocharger for providing inlet combustion air to the air intake manifold, an exhaust gas manifold, and a main radiator heat exchanger. The cooling system comprises: a recipient fluid; a first heat exchanger, separate from the main radiator heat exchanger and disposed upon the engine at a location remote from the main radiator heat exchanger, and having a first passageway defined therein which is fluidically connected to the recipient fluid; a second passageway defined within the first heat exchanger for receiving turbocharged air from the turbocharger, for conducting the turbocharged air through the first heat exchanger such that the turbocharged air undergoes a heat exchange process with the recipient fluid and can be conducted toward the engine intake manifold; a second heat exchanger, separate from the main radiator heat exchanger and disposed upon the engine at a location remote from the main radiator heat exchanger, and having a third passageway defined therein which is also fluidically connected to the recipient fluid; a fourth passageway defined within the second heat exchanger for receiving a fluid from the engine, for conducting the fluid through the second heat exchanger such that the engine fluid undergoes a heat exchange process with the recipient fluid and can be conducted toward the engine intake manifold; and a fan for causing the recipient fluid to pass through the first and third passageways of the first heat exchanger and the second heat exchanger, and for causing the recipient fluid to be discharged to atmosphere.
In another aspect of the invention a vehicle cooling system has an internal combustion engine having an engine block, an air intake manifold, at least a turbocharger for providing inlet combustion air to the air intake manifold, an exhaust gas manifold, and a main radiator heat exchanger. The vehicle cooling system comprises: a recipient fluid; a first heat exchanger, being separate from the main radiator heat exchanger and disposed upon the vehicle at a location remote from the main radiator heat exchanger, and having a first passageway defined therein which is fluidically connected to the recipient fluid; a second passageway defined within the first heat exchanger for receiving turbocharged air from the turbocharger, for conducting the turbocharged air through the first heat exchanger such that the turbocharged air undergoes a heat exchange process with the recipient fluid and can be conducted toward the engine intake manifold; a second heat exchanger, being separate from the main radiator heat exchanger and disposed upon the vehicle at a location remote from the main radiator heat exchanger, and having a third passageway defined therein which is also fluidically connected to the recipient fluid; a fourth passageway defined within the second heat exchanger for receiving a fluid from the engine, for conducting the fluid from the engine through the second heat exchanger such that the fluid from the engine undergo a heat exchange process with the recipient fluid and can be conducted toward the engine intake manifold; and a fan, causing the recipient fluid to pass through the first and third passageways of the first heat exchanger and the second heat exchanger, and causing the recipient fluid to be discharged to atmosphere.
In another aspect of the invention a method of cooling an internal combustion engine is disclosed. The internal combustion engine has an intake air and at least one of a fluid from the engine directed toward an intake manifold. The internal combustion engine has a block being liquid cooled, the intake manifold being connected to the block and has the intake air therein. An exhaust manifold of the internal combustion engine is connected to the block and has the exhaust gas therein. The method comprises: providing a recipient fluid; providing a flow of the recipient fluid; providing an internal combustion engine heat exchanger, the internal combustion engine heat exchanger cooling the liquid coolant within the internal combustion engine and the recipient fluid acting as a recipient fluid for the internal combustion engine heat exchanger; providing a first heat exchanger or an intake air heat exchanger, the intake air heat exchanger being remotely mounted from the internal combustion engine heat exchanger and being mounted to the internal combustion engine, and the recipient fluid acting as a recipient fluid for the intake air heat exchanger; providing a second heat exchanger, the second heat exchanger being remotely mounted from the internal combustion engine heat exchanger, and the recipient fluid acting as a recipient fluid for the second heat exchanger; and providing a connection between the intake air and the at least one of the fluid from the engine to the intake air.